Microphones can be exposed to environments where sound levels, described on a log scale using units of decibels of sound pressure level (dBSPL), can range from very quiet (e.g., less than 25 dBSPL) to very loud (e.g., as high as 140 dBSPL). In addition, microphones are typically required to maintain their performance over a large signal range, e.g., up to 140 dB. Simultaneously, microphones are required to exhibit very small intrinsic noise in order to make weak audio signals detectable, while they also need to handle very large audio signals without significant distortion. As a result, such requirements dictate that microphone have a very large dynamic range. However, implementation of high dynamic range microphones using MEMS techniques and complementary metal oxide semiconductor (CMOS) technologies is very challenging, in part, because of the limited available supply voltage, which is typically less than 3.6 volts (V).
It is thus desired to provide high dynamic range MEMS microphones that improve upon these and other deficiencies. The above-described deficiencies are merely intended to provide an overview of some of the problems of conventional implementations, and are not intended to be exhaustive. Other problems with conventional implementations and techniques, and corresponding benefits of the various aspects described herein, may become further apparent upon review of the following description.